Crimping pliers are used for pressing or crimping a work piece in a tool or die located in a head of the crimping pliers. Such crimping pliers might be used for crimping a connector or electrical contact with an end of an electric wire, wherein an insulation might be removed from the end of the electrical wire before crimping the connector or contact upon the end. The crimping pliers might also be used as working pliers for causing a plastic deformation of the work piece, for cutting or separating parts of the work piece or for punching or stamping the work piece.
Furthermore, it is known to equip crimping pliers with a locator. The locator is used for positioning the work piece relative to the head of the pliers and relative to the tool or dies. The locator guarantees the exact position of the work piece at the start of the crimping process. For one known embodiment, the locator guarantees the correct position of a connector or fitting relative to the wire end freed from the insulation. Furthermore, the locator might interact with the work piece during the crimping process. A locator might also be useful for using the crimping pliers for small work pieces. This is due to the fact that the manual positioning of a small work piece through an opening of the head of the pliers into the tool or die might be difficult or unsuitable for reaching a desired position with a desired small tolerance. When using the crimping pliers for connecting a connector, contact or fitting with a wire end, it has to be guaranteed at the start of the crimping process that both the connector and the wire end have a predetermined relative position to the tool or dies.
The prior art discloses a lot of different embodiments of crimping pliers, transfer mechanisms, kinematics with different degrees of freedom for the components of the crimping pliers moved throughout the crimping process as well as embodiments for locators. All of these known embodiments might be improved by the present invention:
Crimping pliers known from German Patent Application No. DE 27 18 165 A1 have a C-shaped head which is open in lateral direction. Another embodiment of DE 27 18 165 A1 shows dies or tools being moved similar to scissors. For both aforementioned embodiments, the head of the pliers extends in a plane. The pliers have a locator which is pivotable around a pivoting axis between a position for assembly and a working position. The locator comprises a nest for accommodating a work piece. The pivoting axis has an orientation perpendicular to the plane of the head. It is possible to pivot the locator into the position for assembly, introduce the work piece into the nest and pivot the locator with the work piece pinned into or housed by the nest through an open side of the head into a working position. In the working position, the work piece has a defined relative position to the tools or dies. Subsequently, the crimping process plastically deforming the work piece is continued by driving the crimping pliers, here by manually pivoting the hand levers.
Another crimping pliers is distributed by the applicant of the present patent application with the label CS20KS, see FIG. 1. The crimping pliers comprise a C-shaped head being open in one lateral direction. The head comprises a locator having a linear degree of freedom along a shaft fixed at the head, wherein the shaft follows the horizontal leg of the C. Furthermore, the shaft has an orientation parallel to the plane of the head of the pliers. The locator is driven by a lever pivotably linked with the head of the pliers. The pivoting movement of the lever is transferred by a connection between a pin guided in an elongated hole into a linear movement along the shaft.
Furthermore, crimping pliers distributed by the applicant of the present patent application under the label CS25KS (see FIG. 2) comprise a C-shaped head. Here, a locator is pivotably linked with the head having a pivoting axis with an orientation perpendicular to the plane of the head. A pivoting movement of the locator is caused by manually rotating a knurled disc for transferring the locator from a position for assembly to a working position. As shown in FIG. 2, a pivoting movement of the locator requires a manipulation of the crimping pliers with both hands of the user, wherein one hand of the user grips the crimping pliers at the hand levers, whereas the other hand of the user causes the pivoting movement of the locator.
German Patent No. DE 198 32 884 C1 corresponding to U.S. Pat. No. 6,155,095 discloses crimping pliers having a head built with metal plates. Here, the head is O-shaped without an opening in one lateral direction. Caused by an activation of hand levers a movable part or die is moved along a longitudinal axis of the crimping pliers relative to a fixed part of the tool or die. The document discloses a locator being pivoted around a pivoting axis which has an orientation parallel to the plane of the head of the pliers and transverse to the direction of movement of the parts of the tool or dies of the crimping pliers. In a working position, the locator has an orientation parallel to the plane of the head. The locator is pivoted around the pivoting axis from a working position into a position for assembly. The activation of a pivoting movement of the locator requires both hands of a user of the crimping pliers.